On 7/29/07, Mohan2005 <[EMAIL PROTECTED]> wrote: > > Hello: > > we also wish to convert out 32bit dual cores to 64bit dual cores to run java > applications (multiple instances with large JVM memory) > but people advice that 64bit are 20 - 30% slower than the 32bit with smaller > JVM. > why? and if true how to overcome?? >
dont listen to that people they are talking bullshit :-) Leon > thanks > > > > Peter Stavrinides wrote: > > > > Some of arguments presented hold some truths, but look at the bigger > > picture... the point is that 64bit is a superior architecture to 32 bit, > > but it is still maturing... the reasons for this are both hardware and > > software related... the way we write programs will have to change to > > take advantage of the new architecture, and the current generation of > > hardware will no doubt mature to realize the potential of 64bit > > architecture. > > > > 32 bits processors can represent numbers up to 4,294,967,295 while a > > 64-bit machine can represent numbers up to 18,446,744,073,709,551,615. > > For modern hardware to take advantage of the processing power of the 64 > > bit architecture a system must have a minimum 4GB Ram, but probably > > needs significantly more and more importantly the CAPACITY to take full > > advantage of it, allocating it to running processes, with less there is > > potential for lag. > > > > 64bit machines have been around since the 60's but only now are software > > and hardware vendors supporting it for the mainstream market. So is > > 64bit better than 32bit right now? the answer is yes, a 64-bit processor > > has more technology, a better design with more transistors, thus faster > > speeds are possible. This is currently where the true benefit of > > switching to a 64-bit processor lays, it has nothing to do with the > > memory address space, which is exactly that, just space for more complex > > computations. > > > > Peter > > > > > > Alexey Solofnenko wrote: > >> No, each of two 4GB processes will have only a half of the objects > >> under the same load. And I heard that GC does not scale linear with > >> heap size. And this is without multi-threading performance > >> considerations. As usual, your mileage may vary and only tests can > >> tell for sure. > >> > >> - Alexey. > >> > >> Caldarale, Charles R wrote: > >>>> From: Alexey Solofnenko [mailto:[EMAIL PROTECTED] Subject: Re: > >>>> Tomcat with 8 GB memory > >>>> > >>>> I was under impression that GC does not scale linearly. That means > >>>> one 8GB process will be slower than two 4GB processes. > >>>> > >>> > >>> Not true. The time of a full GC using modern algorithms depends mostly > >>> on the number and type of live objects, not the amount of heap space. > >>> The number and type of live (reachable) objects stays relatively > >>> constant for most application once the ramp-up period is over. > >>> Consequently, running a single JVM with the largest heap you can fit in > >>> the process space is the most efficient from a GC point of view. (Of > >>> course, there are plenty of other reasons not to put all your eggs in > >>> one basket.) > >>> > >>> - Chuck > >>> > >>> > >>> THIS COMMUNICATION MAY CONTAIN CONFIDENTIAL AND/OR OTHERWISE PROPRIETARY > >>> MATERIAL and is thus for use only by the intended recipient. If you > >>> received this in error, please contact the sender and delete the e-mail > >>> and its attachments from all computers. > >>> > >>> --------------------------------------------------------------------- > >>> To start a new topic, e-mail: users@tomcat.apache.org > >>> To unsubscribe, e-mail: [EMAIL PROTECTED] > >>> For additional commands, e-mail: [EMAIL PROTECTED] > >>> > >> > > > > -- > > Peter Stavrinides > > Albourne Partners (Cyprus) Ltd > > Tel: +357 22 750652 > > > > If you are not an intended recipient of this e-mail, please notify the > > sender, delete it and do not read, act upon, print, disclose, copy, retain > > or redistribute it. Please visit http://www.albourne.com/email.html for > > important additional terms relating to this e-mail. > > > > > > > > --------------------------------------------------------------------- > > To start a new topic, e-mail: users@tomcat.apache.org > > To unsubscribe, e-mail: [EMAIL PROTECTED] > > For additional commands, e-mail: [EMAIL PROTECTED] > > > > > > > > -- > View this message in context: > http://www.nabble.com/Tomcat-with-8-GB-memory-tf4149367.html#a11853960 > Sent from the Tomcat - User mailing list archive at Nabble.com. > > > --------------------------------------------------------------------- > To start a new topic, e-mail: users@tomcat.apache.org > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > > --------------------------------------------------------------------- To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
